It is worth noting that in 1999, Ford switched the Mustang fuel system to a returnless style, which supplies pressure through a pulse-width modulated (PWM) setup; not all aftermarket pumps work ...

An easy Aeromotive fuel pump install that fits all 1999-2004 New Edge Mustangs.

We install a Paxton's 150 Fuel-Pump Kit in our 1970 Chevrolet Chevelle. Find all the details inside Car Craft Magazine.

2 Of course, in order to replace the fuel pump sending unit, we had to disconnect the exhaust system, unbolt the Panhard bar, and drop the fuel tank.